经纬仪自动调焦电机精密伺服控制技术研究

Research on Accurate Servo Control Technology of Theodolite Auto-focus Motor

调焦电机直流伺服系统的设计是实现电子经纬仪自动调焦的重要环节。针对调焦电机频繁起停换向过程中受摩擦、力矩波动等干扰影响大、难以精确定位和传统PID控制效果不佳等现象,提出了一种基于PIDNN和干扰观测器相结合的直流电机控制方法。在建立三闭环直流伺服系统的基础上,利用了PIDNN兼具神经网络、传统PID控制优点的特性和干扰观测器对各种不确定干扰的观测、补偿作用;并对电机运动特性进行了4-5-6-7插值轨迹规划,以减弱或避免起停冲击和由此带来的振荡。通过对比仿真实验验证了该控制策略的有效性,其响应速度、鲁棒性、抗干扰性和定位精度等性能得到了明显改善。

The design of DC servo system in focus motor control is an important part to realize the electronic theodolite＇s automatic focusing. Focus motor was seriously influenced by various disturbances, such as fric- tion and torque fluctuation, in the frequently reversing process. It was difficult to accurately locate and tradi- tional PID control effect was poor. To solve these problems, a DC motor control method was put forward which combined the PIDNN and disturbance observer. Based on the three closed-loop DC servo system, the PIDNN＇s advantages of neural network and traditional PID control were taken, the disturbance observer＇s a- bility of observation and compensation to uncertain disturbances was functioning. The 4-5-6-7 interpolation locus planning of motor movement was implemented to decline or prevent the start-stop impact and oscilla- tion. The effectiveness of the control strategy was verified by comparative simulation experiment. The re- sponse speed, robustness anti-interference and location precision performance is improved significantly.